<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>待办事项</title>
    <link rel="stylesheet" href="https://cdn.bootcss.com/twitter-bootstrap/4.3.1/css/bootstrap.min.css">
</head>
<body>
<div class="jumbotron jumbotron-fluid">
    <div class="container text-center">
        <h1 class="display-4">JavaScript ToDo</h1>
        <p class="lead">代办事项</p>
    </div>

</div>
<div contenteditable="true">div</div>
<div contenteditable="false">div</div>
<div><div></div></div>
<div class="container">
    <form class="mb-5" action="" onsubmit="return false">
        <div class="form-group">
            <input id="ipt" type="text" class="form-control" placeholder="在此输入任务...">
        </div>
        <button id="btn" type="submit" class="btn btn-primary btn-block">添加</button>
    </form>
    <ul class="list-group" id="ul">
        <li>
        </li>
    </ul>
</div>
<script src="js/script.js"></script>
</body>
</html>